Railroads are important transportation systems for moving passengers and freight. The railroad car wheels are subject to wear and to damage due to material defects, and even sabotage. Many defects worsen gradually and, if detected early, can be repaired or replaced before accidents occur.
An automatic system for detection of such defects, aside of its value as a means for preventing accidents, injuries and deaths, would also allow for train maintenance schedule to be done as indicated by the condition of the wheels, rather than just based on past experience or regulations—an opportunity for cost-saving.
The advent of inexpensive and reliable sensors, microprocessors and electronics makes such automated systems practical and cost-effective.